Wheel axle assembly

ABSTRACT

A releasable wheel assembly includes a bracket having a plurality of bosses, each boss including a hole that receives an axle. A pair of wheels are mounted on the axle and a pair of locking caps fit over respective ends of the axle, the locking caps each including a clip for engaging the axle at a circumferential groove to prevent movement of the locking cap along the axle. The wheel assembly can be mounted to a carry bag or other storage unit by mounting the bracket to the storage unit, where the wheels and axle can be easily removed from the bracket.

BACKGROUND

The present invention is directed to wheel axle assemblies, and moreparticularly to a wheel assembly for moving heavy objects over flat oruneven terrain with the capability of easily removing the wheel assemblyfor the purpose of changing the wheels or for storing the device.

Collapsible shelters such as those offered by International E-Z Up, Inc.have become ubiquitous at parks, beaches, athletic events, and a myriadof other locations where respite from the sun and other elements isdesired. These collapsible shelters are perfect for creating a coveredenvironment during the event, and then the shelter is quickly collapsedinto a compact configuration for transportation. The ease in which theseshelters are expanded and contracted have led to widespread commercialsuccess, but the shelters can be relatively heavy, weighing up to fortypounds or more. For this reason, a carry case with handles is typicallyprovided to make the transportation of the shelter easier. In light ofthe weight factor, however, it may be preferable to roll the shelterwhile in the carrying case rather than carrying the shelter whentransporting the shelter to and from the event. Accordingly, some modelsinclude a protective carrying case or bag that is equipped with small(approximately one inch) wheels that are part of the carrying case andallow the encased shelter to roll along a smooth flat surface. An issuearises, however, when the permanently attached wheels must navigate someirregular terrain such as sand or uneven pavement. The top heavy carrycase can become unstable, making it difficult to roll the shelter.Moreover, the permanent wheels cannot be exchanged for different wheelsif the terrain or conditions suggest a different set.

What is needed is a solution to the transportation of shelters, carryingcases, and other bulk objects in general that includes an exchangeablewheel assembly that promotes movement over a variety of surfaces andterrains, and which can be easily removed when desired such that theunit may be stacked or be stored without the wheel assembly whilefurther permitting the facile change of one set of wheels for another.

SUMMARY OF THE INVENTION

The present invention is a wheel assembly for a case or other bulkobject that includes an axle that can be mounted to a fixed bracket. Thebracket is attached to the bulk object such as a roller bag or carryingcase, and the wheel assembly quickly and easily mounts to the bracketvia bosses extending from the bracket. The axle of the wheel assembly issupported by the bosses to provide a rolling engagement that allows theattached wheels to rotate freely. The wheels in this configuration canbe substantially larger, such as four to six inches or more, to betternavigate uneven surfaces or problematic terrain such as sand or gravel.The wheels on the axle fix the assembly to the bracket through thebosses, such that as long as the wheels are in place the wheel assemblyis reliably secured to the bracket on the bulk object. When the wheelassembly is no longer needed or an exchange of the wheels are desired, afirst wheel is removed from the axle to allow the axle to be slidthrough and out the bosses, leaving only the bracket on the bulk object.In the case of a wheel exchange, the new wheels can be mounted on theaxle and quickly replaced on the bracket.

To secure the wheels to the axle while permitting quick release, thewheels may be locked on the axle with a specialized locking cap placedover the ends of the axle. The locking cap incorporates a two stage clipthat holds the wheel onto the axle when secured to the assembly. Tofacilitate engagement of the clip with the axle, the axle may beprovided with an annular groove between the end of the axle and theouter surface of the wheel. The annular groove is engaged by the twostage clip, which may have a hairpin-like shape including a first stagehaving a semi-circular (or other polygonal or rounded shape) portionwith a diameter/width greater than the diameter of the annular groove onthe axle, and a second stage having a parallel, pinched, or neckedconfiguration wherein opposite sides of the second stage are separatedby a distance that is less than the diameter of the axle and are biasedto bear against the surface of the annular groove. The two stage clipcan easily be manually transitioned from a first position in which theclip is engaged with the axle at the narrowed (second stage) portionthereby fixing the wheel while simultaneously preventing the wheel fromslipping off the axle, to a second position where the larger circular(first stage) portion of the clip is loosely about the axle, permittingthe clip to easily slip off the axle and thereby allowing the wheel tobe removed from the axle. Once a wheel is removed, the axle may beslipped through the bosses on the bracket and the entire wheel assemblyseparated from the bracket.

Other features and advantages of the present invention will become moreapparent from the following detailed description of the preferredembodiments in conjunction with the accompanying drawings, whichillustrate, by way of example, the operation of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front view of a carrying case incorporating a firstembodiment of a wheel assembly of the present invention;

FIG. 2 is an enlarged perspective view of the wheel assembly of FIG. 1;

FIG. 3 is a cross sectional view of the wheel and locking cap of FIG. 1;

FIG. 4 is an exploded view of the wheel assembly of FIG. 1; and

FIG. 5 is a front view, partially in shadow, of the locking cap of FIG.1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 depicts a case 10 for a collapsible shade station, which may be aflexible cloth material or a more resilient sturdy material (e.g.,plastic, aluminum, or the like) as dictated by the needs of the user.The case 10 may include handles 12 along with a zippered opening along atop surface or bottom surface, although other closure means arepossible. Also, while shown in generally a rectangular profile, the case10 may take a number of different shapes and sizes without departingfrom the present invention. Along a bottom edge of the case 10 is awheel assembly 14 that can be quickly and easily affixed to and releasedfrom the case 10 as needed using a quick-release system as describedmore fully below. It is to be understood that while a two-wheeledassembly is illustrated, the invention can be incorporated into multipleother wheel counts, particularly three and four wheeled variants. Thecase 10 preferably includes a stabilizer 15 on the opposite side of thewheel assembly. The stabilizer 15 may include small legs 17 or otherprojections that offset the inclination of the carrying case 10 due tothe presence of the wheel assembly. The stabilizer 15 establishes anoptimum angle of inclination of the carry case 10 when the wheelassembly is in place to make tilting the carrying case easy for rolling.That is, the stabilizer 15 can offer a 10 to 20 degree tilt of thecarrying case 10 with the wheel assembly in place that keeps thecarrying case upright but makes the transition from upright to tilteasier for the user.

As seen in FIG. 2, the wheel assembly 14 includes an “L”-shaped bracket16 mounted to a first bottom edge 13 of the roller bag or case 10 usingrivets 15, snaps, sewn stitches, ties, or other mode of securelyattaching the bracket 16. In the case of rivets 15, the bracket isformed with a plurality of holes that permit the rivets 15 to passthrough and cooperate with matching holes on the surface of the case 10.For a less permanent coupling, the bracket 16 can snap onto the case 10using the appropriate structures (snaps, locking tabs, etc.), althoughthe preferred embodiment is to permanently affix the bracket to the case10 using some rigid connection. The “L”-shaped bracket 16 includes afirst horizontal surface 18 and a first vertical surface 20, where thebottom edge 13 of the case 10 mates with the bracket's horizontal andvertical surfaces 18,20 in a complementary manner. The attachment of thebracket 16 to the case 10 is preferably through both the horizontal andvertical surfaces using fasteners 15 of a particular type to create amore secure coupling of the bracket and the case.

The bracket 16 is formed with a plurality of bosses 22 to carry the axle26 of the wheel assembly. The bosses 22 preferably have a triangularprofile with a rounded vertex, where each boss 22 is equally spacedapart along the bracket 16 and are generally congruent, althoughdifferent thicknesses are possible for end and middle bosses. The bosses22 each include a hole of a diameter selected to accommodate the axle 26of the wheel assembly 14, each hole aligned collinearly with the holesof the other bosses 22. Thus, a single axle 26 can pass through theplurality of bosses 22 of the bracket 16 in such a manner that the axle26 when disposed in the bosses 22 is substantially parallel to the edge13 of the case 10 and parallel to the horizontal surface 18 of thebracket 16. It is to be understood that the number and shape of thebosses 22 are not critical to the present invention as long as the axle26 is adequately supported on the bracket 16 and may rotate freely onthe bracket without wobble or excessive play.

With the bracket 16 secured to the case 10, an axle 26 can be passedthrough the bosses 22 as shown in FIG. 2. With the axle 26 disposed inthe bracket 16 at the collinear holes, a pair of spacers 28 can beplaced over the ends of the axle on the outside of the outermost bossesto center the axle 26 on the bracket 16 and prevent transversedisplacement of the axle when in use. The spacers 28 are preferablycylindrical sleeves with an inner diameter that is slightly greater thanthe diameter of the axle 26 to create a loose fit on the axle, and thespacers 28 have a length such that when both spacers 28 are placed onthe axle 26 on the outside of the bracket 16, the axle still has enoughlength to support at least one pair of wheels 32 and a pair of lockingend caps 30. After the spacers 28 are placed on the axle, a pair ofwheels 32, preferably having a diameter that is at least four inches(4″), are then placed on the axle 26 for rotational movement thereabout.The spacers 28 center the wheels 32 with respect to the case 10,allowing the case to be pulled over both smooth and rough surfaces suchas asphalt, sand, gravel, dirt, etc., with the large wheels 32 rollingeasily over imperfect surfaces.

To secure the wheels 32 to the axle 26, each end of the axle includes acircumferential groove 34 approximately one half to one inch (½″-1″)from the end of the axle 26. The circumferential groove 34 establishes areduced radial dimension when compared with the adjoining sections ofthe axle 26. In a preferred embodiment, the tips on the end of the axle26 adjacent the circumferential groove 34 terminate in a frusto-conicalelement 36 that tapers at the end of the axle. When the wheels 32 andthe spacers 28 are both mounted on the axle 26 about the bracket 16, thecircumferential groove 34 and the frusto-conical element 36 are exposedadjacent the wheel hub 38. The locking caps 30 are then placed over thefrusto-conical element 36 and the circumferential groove 34 to lock thewheels 32 on the axle 26 in a fixed wheel assembly 14. With the wheels32 in place and locked on the axle 26, the case 10 can thusly be rolledover flat or uneven surfaces (such as for example from a vehicle to abeach or grass park), and when the wheel assembly 14 is no longerneeded, one of the locking caps 30 can be removed, the wheel 32 andspacer 28 removed, and the axle 26 slid through the bosses 22 of thebracket 16 to completely disassemble the wheel assembly 14 from the case10. When removed, the case 10 may be stored in a more compactconfiguration without the large wheels 32 taking up unnecessary space.Also, different types of wheels can be exchanged and replaced withlittle effort by disassembling the wheel assembly and simply exchangingone set of wheels for another.

The locking caps 30 are designed to engage the axle 26 at thecircumferential groove 34 using a two-stage clip 40 having two sectionsor stages, an interfering part 53 and a non-interfering part 51 (SeeFIG. 5). When the non-interfering (first stage) part 51 is centeredwithin the locking cap 30, the wire or bar that forms the semi-circularportion does not engage the circumferential groove 34 on the axle 26,permitting the end cap 30 to slide over (and off) the axle freely. Theend cap 30 can be positioned on the axle 26 or removed from the axlewhen the clip 40 is in this position. Once the spacers 28 and wheels 32are mounted on the axle 26, the locking caps 30 are placed over thefrust-conical elements 36 of the axle such that the clip 40 is alignedover the circumferential groove 34. With the locking cap 30 in thisposition, the clip 40 is pushed or otherwise urged from the larger,semi-circular portion of the clip 40 over the circumferential groove 34to the narrower, necked, pinched, or smaller diameter portion of theclip being centered within the locking cap 30 (See FIG. 5). The clip 40in this configuration slips into the circumferential groove 34 and aboutthe axle 26 at its reduced radius, preventing the locking cap 30 fromsliding along the axle 26 and, if the fit between the clip 40 and thegroove 34 is sufficiently tight, will “lock” the locking cap 30 onto theaxle 26 at the circumferential groove 34 (See FIG. 4). The wheelassembly 14 is now fully operational and can be used for its intendedpurpose.

To disassemble the wheel assembly 14, the two stage clip 40 is pulled orotherwise transitioned from the narrow or smaller diameter portion beingcentered over the axle 26 to the larger diameter portion (in thedirection of arrow 90 of FIG. 5), disengaging the clip 40 from thecircumferential groove 34 on the axle 26. In a preferred embodiment, theclip 40 is transitioned by simply pushing a portion 92 a, 92 b of theclip 40 that extends out of the locking cap 30 until the proper stage ofthe clip 40 is engaged or disengaged with the circumferential groove 34on the axle 26. Once the locking cap 30 is disengaged, it can be slidoff the axle 26 and the spacer 28 and wheel 32 removed. The axle 26 canthen be removed from the bracket 16 by sliding it out of the bosses 22in a quick and convenient manner. The wheels 32, spacers 28, and lockingcaps 30 can be stored separately from the roller bag/carrying case 10,conserving space when compared with the assembled configuration.

The locking caps 30 may include a dome-shaped hub cap section 42 tocover the end of the axle, including a frusto-conical aperture 44 sizedto receive the mating end of the axle so as to center the locking cap 30on the axle 26 and establish the correct placement of the clip 40 overthe circumferential groove 34 when the mating frusto-conical elementsare fully engaged. The locking cap 30 further includes a smooth faceplate 46 that bears against the outer hub 38 of the wheel 32 when thelocking cap 30 is locked on the axle 26 to prevent the wheel 32 fromdrifting on the axle. The face plate 46 includes a hole 45 sized toallow the axle 26 to pass through and enter the aperture 44 on the hubcap section 42. The face plate 46 and the hub cap 42 are connected insuch a manner that the clip 40 can enter the path of the axle 26 as itmoves from the face plate 46 to the hub cap 42. This can be achieved,for example, by arcuate connectors (not shown) above and below the hole45 in the face plate 46 that connect the face plate 46 to the hub cap42, but between the arcuate connectors are gaps that the clip's narrowsection 53 to intercede and engage the circumferential groove 34 whenneeded to lock the end cap 30 on the axle 26.

The clip 40 on the locking cap 30 may be a metal rod that is bent orotherwise formed into the two stage clip, although the clip 40 couldtake other forms such as a plate having a cut-out of the shape needed toengage and disengage the axle. The clip 40 is held between thedome-shaped hub cap 42 and the face plate 46 so that it can movelinearly from its first position (disengaged) to its second position(engaged) but is otherwise captured between the two portions of thelocking cap 30. When the clip 40 is in the second or engaged position,the larger diameter section 92 a of the clip 40 protrudes beyond theface plate 46 and dome-shaped cap 30 as shown in FIG. 5. A user can pushdown on the exposed larger section 92 a of the clip 40 in the directionof arrow 90 to force the narrow portion 53 of the clip off thecircumferential groove 34 and thereby disengage the clip 40 from theaxle 26. This action in turn preferably exposes the narrow or smallerdiameter portion 92 b of the clip on the opposite side of the lockingcap 30 while the larger diameter section 51 is about the axle 26. In alike manner, the clip 40 can be engaged by pushing the smaller diameteror narrow section 92 b of the clip so that the clip 40 engages the axle26 at the circumferential groove 34, locking the cap 30 while exposingthe larger diameter section 92 a on the opposite side. In this manner,the locking cap 30 can be quickly and easily engaged and disengaged withthe axle 26 by simply manually pushing on the exposed portion of theclip 40. It is important that the fit between the clip 40 and thecircumferential groove 34 be of a sufficient character that the clip 40will not become disengaged when the case 10 is rolled over rough oruneven terrain, so the press fit should take some effort to engage anddisengage to promote the desired operation.

The invention may be embodied in other forms without departure from thebenefits and characteristics described. The embodiments describedtherefore are to be considered in all respects as illustrative and notrestrictive. Although the present invention has been described in termsof certain preferred embodiments, other embodiments and that areapparent to those of ordinary skill in the art are also within the scopeof the invention.

It will be apparent from the foregoing that while particular forms ofthe invention have been illustrated and described, various modificationscan be made without departing from the spirit and scope of theinvention. Accordingly, it is not intended that the invention belimited, except as by the appended claims.

I claim:
 1. A carry bag for carrying objects, the carrying bagcomprising: a flexible material forming a case, including a zipperedopening; a stabilizer mounted on a first lower edge of the carry bag; abracket affixed the case at a second lower edge opposite the first loweredge; a plurality of bosses defined on the bracket; an axle extendingthrough the plurality of bosses; a first plurality of wheels on theaxle; a plurality of spacers, a first spacer of the plurality of spacersdisposed between a first wheel of the plurality of wheels and a firstboss of the plurality of bosses, a second spacer of the plurality ofspacers disposed between a second wheel of the plurality of wheels and asecond boss of the plurality of bosses, a third boss of the plurality ofbosses disposed between the first boss and the second boss, and the axleextending through each wheel of the plurality of wheels and extendingthrough each spacer of the plurality of spacers; and a locking capadjacent each wheel on the ends of the axle, each locking cap includinga clip adapted to engage a circumferential groove on the axle to fix thelocking cap on the axle.
 2. The carry bag for carrying objects of claim1, wherein the stabilizer orients the carry bag ten to twenty degreesoff vertical when the carry bag is rested upon the stabilizer and wheelassembly.
 3. The carry bag of claim 1, wherein the locking cap includesa hub cap and a face plate, where the clip is disposed between the hubcap and the face plate.
 4. The carry bag of claim 1, wherein the clipincludes a first portion adapted to slide over the axle withoutengagement therewith, and a second portion adapted to engage the axle atthe circumferential groove.
 5. The carry bag of claim 1, wherein theclip is hairpin shaped having a rounded first portion and a neckedsecond portion.
 6. The carry bag of claim 1, wherein the bracket is“L”-shaped having a horizontal surface and a vertical surface.
 7. Thecarry bag of claim 1, wherein the clip can be engaged with anddisengaged from the axle by manually moving the clip in a radialdirection with respect to the axle.
 8. The carry bag of claim 7, whereina portion of the clip extends from a gap between the face plate and thehub cap in both the engaged and disengaged positions.
 9. The carry bagof claim 1, further comprising a second plurality of wheels that can beexchanged with the first plurality of wheels.
 10. The carry bag of claim1, further comprising a second plurality of wheels that are disposed onthe axle adjacent the first plurality of wheels.
 11. The carry bag ofclaim 1, wherein the plurality of bosses have an angular shape and arespaced equally apart.